No explosives were found but the men were ordered to leave the country. Mr Naseer avoided deportation after a judge ruled it was likely he would not be safe if he returned to Pakistan.

Analysis - Laura Bicker, BBC News, New York

Abid Naseer says he's not guilty. He defended himself throughout the trial, but his legal advisers say they'll appeal - and not just against the sentence which they believe is overly harsh. They say this was not a fair trial and Naseer should have appeared in court in the UK, not in front of a jury in a post 9/11 New York.

But US prosecutors say the 29-year-old was capable of mass murder. They say he remains a threat and they're delighted by the sentence. They hope it sends a message to terrorists that they will be caught and they will be put behind bars for life.

Naseer appealed to the judge that he was not - nor had he ever been - a "career criminal". But Judge Raymond Dearie had a response.

"I know you're not," he replied. "You're a terrorist."

UK officials arrested him again in 2010 at the request of US prosecutors.

In 2013 he was extradited to the US, where prosecutors argued Naseer was part of a broader al-Qaeda conspiracy to attack various Western locations, including the New York subway system and a newspaper office in Copenhagen, Denmark.